by
Hall, Prentice

Answer

h=21t+40
The height of helicopter after 45 seconds will be 985 ft

Work Step by Step

h is the height of a helicopter, and it increases by 21 feet everytime for each second and since the helicopter started the climb at 40 feet above the ground, the function rule should be h=21t+40
To find height after 45 seconds plug it in the equation.
h=21t+40
h=21(45)+40
h=945+40
h=985 ft